Air conditioning apparatus for passenger cars



June 15, 1937. w. J. MADDEN AIR CONDITIONING APPARATUS FOR PASSENGER CARS Filed March 9, 1956 2 Sheets-Sheet 1 ORNEYS.

WiZZmm J Maddam June 15, 1937. w MADDEN AIR CONDITIONING APPARATUS FOR PASSENGER CARS Filed March 9, 1956 2 Sheets-Sheet 2 I N VEN TOR William J Maddmy B Y WITNESSES:

Patented June 15, 1937 AIR CONDITIONING APPARATUS FOR PAS- SENGER CABS William J. Madden, Lansdowne, Pa., assignor to The Pennsylvania Railroad Company, Philadelphia, Pa., a corporation of Pennsylvania Application March 9, 1936, Serial No. 87,803

3 Claims; (01. 62-103) This invention relates to air conditioning railway passenger car of the day-coach type, and systems, and more particularly to a system although the invention is thus illustrated as apadapted for incorporation in a railway passenger plied to a particular type of car, it will be undercar. stood that the invention is equally applicable Heretofore it has been proposed to utilize space to many other forms of passenger carrying cars. in the upper regions of a passenger car near the The car body comprises, generally, a roof I, a roof to accommodate certain of the elements of floor 2, and side walls 3. The car includes the air conditioning equipment, such as blowers, usual end doors 4 and windows 5, preferably filters, and surface cooling means, and to locate having double sashes, the windows being kept the remaining elements of the system beneath closed in order to establish a substantially closed 10 the car. One objection to such an arrangement system with controlled admission of quantities is that it requires a number of relatively long of fresh air. pipe lines to conduct the refrigerant from the In the illustrated example, the two ends of refrigerating apparatus beneath the car to the the car are formed in like manner, each end cooling means at the roof thereof through which being provided with air conditioning equipment. 15 the air is circulated, and unless such pipe lines Accordingly, a description of the structure and are well insulated, there is an obvious sacrifice apparatus applied at one end of the car will in eiificiency. Another objection to such an arsufllce to give a complete understanding of the rangement is that it renders a large part of the improvements of this invention. At the end of air conditioning equipment inaccessible for the car a central passageway 6 leads from the maintenance and inspection. and door I to the passenger space 1. In the One object of the present invention is to procustomary manner, rooms 8, 9 are provided at vide an improved arrangement of the elements each side of the central passageway 6, and it may of the air conditioningequipment with relation be assumed, by way of example, that the room to the car structure which avoids the above re- 8 constitutes a toilet and the room 9 a lavatory, 25

cited disadvantages. though obviously these rooms may be used for Another object of the invention is to provide any desired purpose. Above this region of the an air conditioning system which requires a car there is formed a monitor deck having a minimum of alteration or re-arrangement of the horizontal ceiling plate II and transverse bulk car, and one which is compact, readily accessiheads l2, l3, which define with the roof I of 30 ble and of simple and inexpensive construction. the car a substantially closed overhead com- Another object of the invention is to provide partment. a system in which quantities of fresh air from Between the central passageway 6 and one outside the car are admitted and mixed with side wall 3 of the car, there is formed a comquantities of air withdrawn from the passenger partment it which is relatively narrow in the 35 space prior to conditioning, and in which imdirection of the longitudinal axis of the car,

1 proved means are provided for mixing together but which extends transversely for the full such fresh air and withdrawn air. space between the passageway 6 and the car Other objects and advantages characteristic side 3. The compartment it forms a vertical 40 of my invention will become more fully apparent duct, and has near the base thereof, as clearly 40 from the description hereinafter set forth of one shown in Fig. III, an intake l5 situated at the example or embodiment of the invention as apside wall of the car and adapted to admit fresh plied to a conventional railway passenger car, air from the exterior, and an intake l6 situated having reference to the accompanying drawat the central passageway and adapted to reings. Of the drawings: ceive air withdrawn from the passenger space 45 Fig. I represents a plan view of a railway pas- 1. Associated with each intake l5, I6, there is senger car embodying my invention, with a pora filter l5a, lGa which serves to clean air passtion of the car roof broken away to reveal the ing therethrough. interior. At the base of the compartment Hi, there is a- Fig. II represents aside elevation of the same, mixing chamber Ill having guiding surfaces l1, I8 50 with a portion of the side wall broken away to which deflect the incoming air upwardly and reveal the interior; and, toward the center of the compartment It in the Fig. III represents an enlarged cross section, manner clearly illustrated in Fig. III. These surtaken as indicated by the lines lII-III of Fig. I. faces i1, 18 also serve to prevent cross flow of air In the drawings there is shown a conventional from the fresh air intake I5 across the mixing chamber l and through the opposite intake Hi The operation of the apparatus of this invenwhen strong lateral wind currents are encountered. Additional surfaces I9, 20 serve as baflles and obstruct direct upward flow of currents of air along the sides of the compartment. A horizontally disposed tray 2| is located centrally within the compartment l4 and serves also as a deflecting baille. The tray 2| and oppositely disposed baffles I9, 20, form restricted passageways for the upfiowing air. At each side of the tray 2|, additional air guiding surfaces 24, 25 are formed, and these surfaces direct the upwardly flowing air currents around the tray towardthe central axis of the compartment. The various baffles and air guiding surfaces thus described are so formed and arranged that the incoming fresh air passing through the intake I5 is directed across the path of the incoming air withdrawn from the passenger space through the intake 16. Moreover, the formation of the baffles and guiding surfaces is such that, in order to pass beyond the tray 2|, the air currents are caused to swirl with centrifugal motion and to change their course of direction. Suflicient turbulence is thus created in the mixing chamber l0 that the fresh air is thoroughly mixed with the air withdrawn from the car prior to admission to the cooling means 26. g

The cooling means 26 may comprise any convenient form of heat interchange apparatus. As shown in the drawings, the cooling means 26 takes the form of a continuous pipe 21 having a series of U-bends and having projecting fins 28 through which heat is readily absorbed from the air. The refrigerant flowing through the surfacecooler 26 may be of any desirable character such for example as ice water. Apparatus for refrigerating the medium flowing through the surface cooler 26 is conveniently located beneath the floor 2, and such apparatus, being well known in the art, is not illustrated herein. Moisture deposited on the surface cooler 26 falls by gravity to the tray 2| where it is collected and from which it is discharged through a drain pipe 29.

Air discharged from the surface cooler 26 is drawn into a blower 30 driven by an electric motor 3|.

' 30, there is provided a duct 32 which leads from the upper region of the compartment l4 through the monitor deck, diagonally to the transverse bulkhead i3 where it terminates in an outlet grille 33, preferably disposed above the central passageway 6. All of the conditioned air is forced by the blower 3|! through the duct 32 and discharged into the passenger space I of the car at the outlet grille 33. The distribution of air thus discharged within the passenger space 1 is represented by the arrows in Fig. II.

In the wall of the compartment l4 adjacent to the central passageway 6, there is a panel or door 34 which may be opened or removed to give access to the apparatus within the compartment. At the center of the car roof, there is desirably provided a continuously operated exhaust fan 35 which assists in promoting circulation of the air within the passenger space I from each end along the roof toward the center of the car.

In order that the system herein described may be used in the winter season for the purpose of heating the air, as well as in the summer season for the purpose of cooling the air, there is provided within the air conditioning compartment H a heating unit 31 which is desirably located immediately above the cooling means 26 and which may take the form of an ordinary radiator.

At the discharge side of the blower ion, in the summer season, is as follows. The motor driven blower 30 is continuously operated and serves to draw quantities of fresh air from the exterior of the car through the intake I5, as well as quantities of air from the passenger space 1 through the central passageway 6 and the intake l6. Currents of fresh and recirculated air are thoroughly mixed together in the mixing chamber In, the various bafiles and guiding surfaces creating a suflicient turbulence of the air in its passage around the tray 2| so that before admission to the surface cooler 26 substantial heat exchange has been effected, the outside air being thus precooled prior to contact with the. fins 28 of the surface cooler. The combined fresh and recirculated air, after passage through the surface cooler 26, is drawn into the blower 30 and carried through the duct 32 to the grille 33, from whence it is discharged into the passenger space near the roof of the car. Simultaneously, the exhaust fan 35 removes from the upper region of the car quantities of vitiated air at the region of the car where such air is most likely to be concentrated. In the winter season the operation of the system is substantially the same except that the heating unit 31. is used instead of the cooling unit 26.

It will be particularly observed that all of the air conditioning apparatus, except those parts which are located at the underside of the car, is housed within a relatively small compartment taking up a minimum of revenue space in the car, and that said compartment is readily accessible. The electrical controls for the unit may be located within or near the air conditioning compartment, making the entire apparatus very compact and easy to inspect or repair. The eiiiciency of the apparatus is increased by reason of the special character of the mixing chamber within which the air is precooled prior to delivery to the surface cooler.

While I have described one example of the practice of this invention, as applied to a particular type of railway car, it will be apparent that the apparatus may be applied to various types of passenger cars, and that various changes may be made in the form of the apparatus disclosed, without departing from the spirit of the invention as defined in the annexed claims.

Having thus described my invention, I claim:

1. In a railway passenger car, a compartment for air conditioning equirment, said compartment having a. mixing chamber at the base thereof near the floor level of the car with an intake for fresh air from the exterior of the car and an intake for recirculated air from the passenger space, cooling means disposed above said mixing chamber, means for drawing air through said intakes and said cooling means and then discharging it into the passenger space, and baffling means projecting within said mixing chamber and associated with each said intake, said baiiling means being so disposed as to obstruct cross flow of air from said fresh air intake to said recirculated air intake and so directed as to cause the currents of fresh and recirculated air to cross each other in their passage upwardly through the mixing chamber, whereby said currents, of air are mixed and retarded prior to admission to said cooling means.

2. In a railway passenger car, a compartment for air conditioning equipment, said compartment having a mixing chamber at the base thereof near the floor level of the car with an intake for fresh air from the exterior of the car and an intake for recirculated air from the passenger space, cooling means disposed above said mixing chamber, means for drawing air through said intakes and said cooling means and then discharging itinto the passenger space, and hauling means including deflecting surfaces associated with each said intake for obstructing crossflow of air from said fresh air intake to said recirculated air intake and for guiding and directing the currents of fresh and recirculated air whereby they cross each other in their passage upwardly through the mflxing chamber, and a solid protective baiile forming the top of said mixing chamber and causing the air currents to diverge in their passage around said baffle and then to converge prior to admission to said cooling means.

3. In a railway passenger car, a compartment for air conditioning equipment, said compartment having a mixing chamber at the base thereof near the floor level of the car with an intake for fresh air from the exterior of the car and an intake for recirculated air from the passenger space, cooling means disposed above said mixing chamber, means for drawing air through said intakes and said cooling means and then discharging it into the passenger space, and baifling means including deflecting surfaces associated with each said intake for obstructing cross flow of air from said fresh air intake to said recirculated air intake and for guiding and directing the currents .of fresh and recirculated air whereby they cross each other in their passage upwardly through the mixing chamber, and a solid protective baflle forming the top of said mixing chamber and causing the air currents to diverge in their passage around said baflle and then to converge prior to admission to said cooling means, said solid protective baflie being in the form of a. tray and serving to collect moisture deposited by said cooling means.

W'IILIAM J. MADDEN. 

